This circuit is for traditional old-style telephone lines found in an American 1980s documentation. Components are common and the optical coupler can be replaced with an equivalent.
This circuit was found in an English magazine from 1978, but it is still current, just change the...
This circuit causes a buzzer to emit an intermittent tone when the temperature sensed by the...
This microcontrolled null adjustment for operational amplifiers was obtained in a Linear...